The Knicks are getting a big man back for Christmas, and it’s not Amar’e Stoudemire.

Camby, signed as the Knicks’ backup center, said before yesterday’s win over the Timberwolves he is returning for tomorrow’s game against the Lakers after missing the last 12 games with plantar fasciitis.

The Post reported Camby took a cortisone shot last week to ease the pain. His preseason was ruined by a calf strain, then when he got healthy in November, Woodson often didn’t use him. Now Woodson needs him with Stoudemire leaning against playing on the three-game West Coast trip and Rasheed Wallace still “day to day’’ with a sore foot.

Camby said his return comes at a perfect time because Tyson Chandler needs some time to rest. That’s what Camby signed up to do.

“I’m ready to compete,’’ Camby said. “We have to find time to get Tyson some rest. He’s been playing exceptional basketball. We need to find time to get him minutes.’’

Camby confirmed he took a cortisone shot last week and most of the pain is gone.

“No one’s pain free at this point no matter how many cortisone shots you take to mask things,’’ he said.

With Wallace still not expected back tomorrow, Camby finally can make an impact after Woodson held him out of some games in November.

“I’ve been available,’’ Camby said. “I just had to get my number called. I’ll be available for whenever they can use me.’’

Camby said it’s been “frustrating’’ he has played in just six games.

“I’ve been a starter my whole career,’’ he said. “And coming here and not getting the opportunity because of my calf in preseason. … At this point I’m not asking for a lot of minutes. I’m just looking forward to this trip.’

* Stoudemire’s knee soreness after his two practices with the D-League was enough to convince him he probably isn’t ready for tomorrow and likely the three-game West Coast trip.

Coach Mike Woodson had hoped to hear differently. “I don’t think he will be available,’’ Woodson said. “My talk with Amar’e first and foremost was about: ‘Are you healthy enough to play?’ He’s still not at that stage. He’s still in the process of feeling good about himself when he’s out there working out. And we’ve got some practice days coming up when we come back [from the trip].

“And I think that would be a good time to get him out on the floor, running and banging around with his own teammates, and just see where he is.”

Asked if they considered him playing a D-League game, which he is allowed under the new collective bargaining agreement, Woodson said, “I’d rather have him here [to play] with us than to do that.”

* Wallace was on the court shooting yesterday before the game — a sign of progress. He could return later on the West Coast trip after missing his fifth straight game yesterday.

The Knicks termed the injury Saturday an “acute stress reaction’’ in his foot and chronic condition. A Knicks official said a published report Wallace has a stress fracture is “erroneous.’’ A stress fracture would have put Wallace out approximately two months. A stress reaction can’t be found on an MRI exam or X-ray whereas a stress fracture can.

The Knicks said they have rested Wallace, fearful a stress reaction can worsen into a much-more serious stress fracture. Wallace repeatedly has said he had reaggravated an old injury.